160 PROCEEDINGS OF THE AMERICAN ACADEMY 



bus ; umbella in macrioribus simplici, in vegetioribus (TV. Kootenay, 

 &c. Lyall) iterum iterumque divisa. — Flowers smaller than in E. um- 

 bellatum and pale, with a proportionally longer stipitiform base. 



17. E. umbellatum, Torr. in Ann. Lye. 2, p. 241, & in Sitgreaves, 

 Rep. t. 12 (mala quoad fl. et embryo). Spithamaeum ad pedalem ; ra- 

 mis sterilibus decumberitibus vel repentibus saape stoloniformibus laxe 

 crespitosis apice fasciculato-foliosis ; foliis obovato-spathulatis ovalibus- 

 que in petiolum angustatis subtus albo-lanatis ; pedunculis scapiformibus 

 prater bracteas foliave umbellam siraplicem raro subcompositam invo- 

 lucrantia aphyllis ; involucro profunde 6 - 8-fido ; perigonii flavi nunc 

 albi segmentis stipite gracili 2 - 3-plo longioribus ; embryonis cotyle- 

 donibus fere orbiculatis radicula vix incurva parum brevioribus. — 

 Plains of Nebraska to Oregon, Nevada, and the borders of California. 

 E. stellatum, Benth. Eriog. (probably included a small form of the 

 preceding), Hook. Fl. Bor.-Am. t. 177, a northwestern form, repre- 

 sented with the scapes all unifoliate ; but this leaf is extremely excep- 

 tional, and the whorl of leaves at the middle mentioned by Bentham in 

 DC. Prodr. we have not met with. Var. majus, Benth. in DC, is 

 merely a large state. E. ellipticum, Nutt. PI. Gamb., is the same, 

 with the umbel compound, which is uncommon. And there are three 

 or four other unpublished Nuttallian names for the species. Green and 

 glabrate or almost glabrous forms have been collected by Prof. Brewer, 

 S. Watson, and others. The most reduced and diminutive form is 



Var. monocephalum (E. Tolmieanum, Hook. Fl. Bor.-Am. 2, p. 

 134) : pusillum, casspitoso-depressum ; foliis supra vel utrinque glabra- 

 tis, lamina £ - £-pollicari ; scapo \ - 3-pollicari gracili apice involu- 

 cra 2-4 capitata saspius 1 - 3-bracteata vel unicum plerumque nu- 

 dum majus gcrente ; floribus pi. m. minoribus. — Oregon on the Walla- 

 Walla among Wormwood, Tolmie. Humboldt and Clover Mountains, 

 Nevada, alt. 9-10,500 feet, S. Watson. Sonora Pass, California, 

 10,000 feet, Brewer. Uintah Mountains, Utah, 9-10,000 feet, S. 

 Watson. Some forms have green and almost wholly glabrous leaves. 



-H- h — h- Herbse lana tenui densa incanas ; scapi, e caudicibus ramisve 

 sterilibus crespitosis ut in praecedentibus orti, prorsus aphylli, gra- 

 cillimi, umbellam simplicem parvi-involucranti-bracteatam gerentes, 

 involucro centrali semper sessili ! Flores minores et pauciores 

 in involucro 5 - 7-dentato, basi breviter stipitiformi, subdioici, 

 umbella mascula contracta capitata. Filarnenta basi et ovarium 

 apice saapius pubescentia. 



